53173721 has 2 divisors, whose sum is σ = 53173722. Its totient is φ = 53173720.

The previous prime is 53173709. The next prime is 53173727. The reversal of 53173721 is 12737135.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35868121 + 17305600 = 5989^2 + 4160^2 .

It is a cyclic number.

It is not a de Polignac number, because 53173721 - 2¹⁴ = 53157337 is a prime.

It is not a weakly prime, because it can be changed into another prime (53173727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 26586860 + 26586861.

It is an arithmetic number, because the mean of its divisors is an integer number (26586861).

Almost surely, 2^53173721 is an apocalyptic number.

It is an amenable number.

53173721 is a deficient number, since it is larger than the sum of its proper divisors (1).

53173721 is an equidigital number, since it uses as much as digits as its factorization.

53173721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4410, while the sum is 29.

The square root of 53173721 is about 7292.0313356430. The cubic root of 53173721 is about 376.0385339450.

The spelling of 53173721 in words is "fifty-three million, one hundred seventy-three thousand, seven hundred twenty-one".